[ZX12R]

If top kill fails they plan to immediately cut off the BOP with a diamond saw blade

Did you mean to say cut off the riser? I don't think cutting off the BOP would be an option at the moment.

[Williams]

of course I dont know my terminology but from the diagrams they would cut the pipe just below the device sitting on top of it (which I thoght included removing the BOP), there would just be the pipe and they would attempt to connect to that.

[jpsb]

You are correct, next “plan” is BOP on top of BOP. might work but it is going to be one hell of a balancing act. 4 story 250 ton structure on top of 4 story 250 ton structure.